I've been riding belt-drive bikes across
continents since 2010, and after more than 100 thousand kilometres across 100
countries, I'm ready to tell you there is no better touring, bikepacking or
commuting drivetrain available. I've taken belts across the hottest deserts,
into icy snowfields, through dense jungles, along beaches, up muddy tracks
and to the top of the highest road in the world. I suspect there are few people
on Earth with the same real-world experience as me. In this video, we'll
look at what belt drive is, what the advantages and disadvantages are, and
then I'll go through the frequently asked questions to make sure no rock is
left unturned. Oh, and this is not a sponsored video, I
haven't invested in any belt drive businesses and I am free to use chains
on my bikes at any time. I'm just a big old fan of belts and I hope you can soon
see why. So, what is belt drive? Belts are used to run the blowers on 10,000
horsepower racing engines, the power trains of 150 horsepower motorbikes and
more recently the drive trains of many bicycles. Gates Corporation invented
their first automotive bolts about a century ago, and today, they're the most
popular brand of belt system for bikes. The belts themselves are made from a
polymer that is reinforced using multiple carbon-fiber cords. They are
then usually paired with stainless steel cogs and durable alloy chain rings. And
why do I think belts are the best drivetrain? Number one, belts have a very
long service life. You can expect a belt drivetrain to last three to four times
longer than a typical chain. That's upwards of 30,000 kilometers, even in the
poor riding conditions you often see me flailing about in! Additionally, they're
impervious to water and salt, so there's no rust here, even after months of
cycling through intense wet seasons. Number two, belts require little to no
maintenance. Belts do not stretch, they do not require lubrication,
they are never greasy and they do a surprisingly good job of clearing the
mud. Just a splash of water is usually enough
to keep them going. Number three, belt drive trains are
perfectly silent. You know when your chain is freshly cleaned and lubed and
running perfectly silent? Well, that's about pretty much all of the time! Number
four, belts are lighter than chains. You can
expect a weight saving of between 100 and 300 grams when compared to chain
drive. The upsides are looking pretty darn good, but what about the downsides?
Number one, you cannot use belt drive with derailleurs. A belt is designed to run
in a perfectly straight line. That means it cannot be paired with derailleurs, chain
rings or cassettes, but it can be used with a gearbox at the crankset or an
internal gear hub at the rear wheel. Number two, you need a belt compatible
frame! As belts are usually one-piece, your frame will need to be designed with a
belt splitter in the rear triangle so that you can fit a belt to your bike. The
frame also needs to be 'stiffness test approved' to ensure that the frame will
not flex sideways too far, causing the belt to wander off the rear
cog. Number three, replacement parts and not found in typical bike shops. I
personally have never found this to be a problem, I buy all of my spare parts
online and I always carry a spare belt for emergencies. I usually travel for 18
months before I even start thinking about ordering replacement parts. Number
four, there's a higher upfront cost. A belt drivetrain is not super cheap, but
they are cost-efficient provided you get the full mileage out of your belt
drivetrain. I've estimated you'll go 125 kilometres per dollar. This is the
equivalent of a chain drivetrain costing you about $60 per 7500 kilometres. For
reference, that's the same price as the longest-lasting chain we have, which
wears out at between 5,000 and 7,000 kilometres. And number 5, it's a less
efficient drivetrain. Derailleurs are undoubtedly the most efficient drive
trains available with an average drive efficiency across all gears of between
95 and 98 percent. As you need to employ a gearbox
system on a belted bike, there will always be additional frictional losses.
According to the data we have, Shimano internal gear hubs and Pinion gearboxes
are a bit over 90 percent efficient, while the Rohloff hub jumps to over 94
percent efficient. The efficiency discrepancy is one of the
reasons you rarely see gearbox and belt drivetrains on race bikes. There can be
additional resistance at the belt too, but it's a much smaller percentage than
the gearbox itself. Let's move on to all of the frequently asked questions you
might have about belt drivetrains. How does Gates Carbon Drive feel to ride? It rides just like a well-lubricated chain, but it has a slightly different
humming sound. And, despite its looks, it feels just as stiff and solid to ride as
a chain. How do you repair a belt? It's very easy to remove a chain link on the
side of a trail. Belts on the other hand are designed to be replaced. Rather than
carrying a chain tool, it's prudent to carry a spare belt which coils down into
a small enough size. I've broken just 31 thousand kilometre old belt in the last
10 years, so emergency belt replacement never actually crosses my mind. When do
you know a belt is too worn? Surprisingly, it's the rear cog that wears the fastest on
a belt drivetrain, the teeth can get very, very pointy! Given that I stray pretty
far from services I usually swapped my entire drivetrain
out as a precautionary measure at about 30,000 kilometres. I've never actually
found the true distance limit where the belts cease to work, but it looks like
the lifespan may have just been extended as Gates has just introduced a new high-hardness steel cog this week! What's the deal with belt resistance? Perhaps you've
seen videos of people stacking weights on pedals to show the difference in
drive resistance between a belt and a chain. These tests are a bit misleading
because chain and belt friction increases at different rates - the belt
slope is actually four times less steep. There is a crossover point where a belt
becomes more efficient than a chain, it's when you're pedalling at two
hundred and twelve watts. This is a bit higher than the typical cyclist pushes,
so expect around half a watt penalty on the belt system in ideal riding
conditions, but likely a better efficiency in adverse conditions due to
the way a belt can remove debris from the cogs. That said, if you use a
particularly stiff frame, you can lower the belt tension below the
recommendation. You didn't hear this from me, but I've been slowly reducing the
belt tension on my Koga over the last year, and frankly, it's getting ridiculous.
My belt can now touch my chainstay, it is so far beyond the minimum that I can't
even measure it! And I'm a very strong rider, with a very heavy load, riding up
incredibly steep mountain roads. At my approximate belt tension and at the
power outputs I push, my belt is likely running the same or lower friction than
a chain. I only recommend trying this with a belt snubber fitted which will
make sure the belt stays on, even if the belt tries to skip. So, what is the actual
maintenance like? If you ride in adverse conditions, it's a great idea to use a
toothbrush and water to clean any debris off the system - if only to reduce the
wear on your cogs. In dry conditions with very fine dust, a belt drivetrain can
sometimes make an infuriating squeaking sound. This is very easily remedied by
using a silicone spray which immediately dries onto your belt.
I am currently experimenting with treadmill silicone lubricant which stays
wet a bit longer, attracting more grit in the short term, but it seems to require
fewer applications. Rohloff biodegradable chain lube is known to
work similarly. Just make sure to skip the Hanseline belt care stick, it's
extremely sticky, and frankly, a terrible product for a belt. How do you adjust the
belt tension? Unlike chains, belts do not get longer
over time, resulting in a true set-and-forget drivetrain. There are two
typical ways to set the tension of a belt. Some bikes use sliding rear dropouts, but
from speaking to a handful of bike engineers,
it sounds like an eccentric bottom bracket shell allows for the stiffest
possible rear triangle for running the lowest possible belt tension.
You can use your smartphone to appropriately determine the tension of
your belts. By plucking the belt, your smartphone app will decipher the tension
frequency and determine if your belt tension is correct. As you can see, my
belt falls below the frequency range. But if we tension everything up, we can get a
reading. Don't belts destroy bearings? It's
possible that a belted bike with the maximum belt tension could prematurely
wear bearings. But on a bike engineered for belts, the frame will be stiff enough
so that the tension is the equivalent of a rider using a chain and pedalling at
250 watts, which is not at all that unusual.
Aren't there limited gear ratios available? There are four rear cog sizes,
there are four sprocket sizes and there are twenty belt lengths to choose from.
This should not at all be limiting for the purposes of touring and commuting.
Can you modify a frame for belt drive? I have taken two touring frames to a custom
frame builder to get rear belt splits installed in the rear triangles. They
have worked just fine but I've had to use a high belt tension as the rear
triangles had more side-to-side flex than a dedicated belted frame. Are there
any other belt companies? Gates completely dominate the market when it
comes to belt drivetrains, but there are a few manufacturers offering
alternatives, including Veer, Accord and Driveline. Veer looks to be the most
promising and has one big advantage over Gates - their belts are able to split,
which means that you can fit them to any bike! As the rear triangles of a typical
bike and not designed to be particularly stiff,
I suspect the Veer system will have a high friction when retrofitted to a bike.
But that said, you still get all the advantages of belt drive, so I think it's
a really cool product if your belt curious and don't want an entirely new
bike. Let's wrap this up! I hope this information has hit every
possible belt talking point. I have put belt drivetrains through the wringer
for 10 years, taking them into the world's most remote locations, and I'm
certain there is no better drivetrain available for touring, bikepacking and
commuting. If the idea of a gearbox system like the Rohloff or Pinion is compelling to you, definitely skip the chain option and pair it with
belt drive. They are incredibly long-lasting, virtually maintenance-free,
lightweight and silent to ride. You can support this content over on Patreon, you
can follow me @cyclingabout on Instagram and Facebook,
check out the Bikepacking Bike Buyer's Guide and the Touring Bicycle Buyer's
Guide, learn cool shit on CyclingAbout.com, leave a comment below, and here's a
challenge - try and convince me that chains are better than belts!
